Menu Sign In Contact FAQ
Banner
Welcome to our forums

Parts and Materials Substitution for vintage a/c

The FAA has an interesting advisory circular (23-27) in place under this title.
The introduction reads like this :
This advisory circular (AC) provides guidance for substantiating parts or materials substitutions to maintain the safety of old or out-of-production general aviation (GA) aircraft, or other GA aircraft where the parts or materials are either difficult or impossible to obtain. This AC also provides guidance about the data required to gain Federal Aviation Administration (FAA) approval for making these substitutions. This AC does not include specific approvals for installations. It provides guidelines to follow when collecting information needed for an FAA approval. The material in this AC is neither mandatory nor regulatory in nature and does not constitute a regulation. You may follow an alternate FAA-approved method. However, ifyou use the means described in this AC, you must follow it in all respects. Mandatory words such as “must” apply only to those who seek to show compliance to a specific rule by use of a method prescribed in this AC without deviation.

Obviously this is FAA only, but I wonder if anybody knows of similar guidelines, projects or else by EASA for EASA territory.
Thanks

AJ
Germany

AJ wrote:

Obviously this is FAA only, but I wonder if anybody knows of similar guidelines, projects or else by EASA for EASA territory.

I guess in EU-land that refers to what is called Orphans, they are either moved to National Permit to Fly (PtF) or EASA restricted airworthiness certificate (RCoA), in the UK the parts substitution story for the former is largely under LAA engineering oversight while for the latter it seems covered in EASA Part MA.501/Part 21.A.307?

ESSEX, United Kingdom

@Ibra
This might be the answer when it comes to “type of aircraft / type of airworthiness certificate”.

But I am looking for procedures related to parts and materials, or guidelines released by EASA on the same subject. May be such don’t exist because it simply is national business (and not EASA business). In this case, whatever is applied or applicable in one member-state, wouldn’t help in another. Fragmented regulatory realms.

AJ
Germany

If the aircraft is certified then any mods must follow the usual route for that, for which there is a Minor and a Major route and this is true under both EASA and FAA (though the two differ in many respects).

There are many people here who have been involved with developing paperwork for the EASA version of these mods. Usually they sell the mod paperwork package to installers/dealers. This in turn generates “forum political” issues when one of these installers (i.e. their typical customer) gets “blown” following a less than stellar job, and these reverberate for years…

If the aircraft is not certified then the regime which governs it is a national one. In the UK it is the LAA, which has a delegated authority from the CAA. In most/all other countries it is their national CAA which has a “homebuilt” department which runs this stuff. In say France it is the DGAC.

Most people are happy that EASA is not involved although a significant minority would be very happy to see EASA involved if it meant they could fly Europe-wide, IFR, etc, without the hassle of the permit system. But this is the political quid pro quo; you cannot have it both ways.

The FAA is much better than EASA when it comes to orphaned types. In Europe these cannot really exist, if the TC holder disappears. One thread was here. In the US, if the TC holder disappears, everybody carries on as before. Even on certified types there are usually several ways to do a mod or a repair. However, getting FAA Major mods done for a European based N-reg is not trivial; I’ve done several of these and you need good contacts.

Administrator
Shoreham EGKA, United Kingdom

AJ wrote:

Obviously this is FAA only

I don’t think so. Haven’t this been discussed before sometime on this board? As long as the original aircraft is ICAO and kept that way, it doesn’t matter under which “regime” it is maintained, or where. It’s a different matter if it is taken out of certified standard.

ENVA ENOP ENMO, Norway

LeSving wrote:

I don’t think so. Haven’t this been discussed before sometime on this board? As long as the original aircraft is ICAO and kept that way, it doesn’t matter under which “regime” it is maintained, or where. It’s a different matter if it is taken out of certified standard.

@LeSving
When I said “FAA only” I meant to say, this document (AC) is FAA and explains the FAA approach. It is of course possible, and that’s what I am trying to understand, that the approach is applicable to ICAO planes all over the world, or in some similar form to EASA reg planes.
But I haven’t been able to find this in earlier posts. If you were able to remember where and how …, or if you had some other reference that would help a lot. Thanks !

AJ
Germany

We had a discussion about this, but where, and what to search for?

The thing is, they are NOT EASA planes, and never will be. But they are ICAO (or perhaps not. In that case none of this apply). This means they are on national regs, and maintained according to a national “regime”. You have to look at what the relevant national regulation has to say about this. In Norway it means a part/material may be substituted on approval by the CAA, or by an approved organisation, or done as a production of a set of parts. Standard parts and smaller structural parts can be made/replaced by the one doing the maintenance. Only “aviation grade” materials can be used for standard parts (whatever that means).

ENVA ENOP ENMO, Norway

I think one can get wrapped up in circles.

There are extremely few planes which have an ICAO CofA but are classified as NON EASA, and which are useful for anything.

Such planes have great value to the right people because – being NON EASA – they can be maintained in Europe as “homebuilt” (or “experimental” if you prefer) but – being ICAO certified – can fly worldwide without needing any permits, potentially IFR too.

One related thread is here.

Administrator
Shoreham EGKA, United Kingdom

Peter wrote:

Such planes have great value to the right people because – being NON EASA – they can be maintained in Europe as “homebuilt”

I don’t think that’s true. The Piper Apache for instance has an ICAO CofA, but is non-EASA. The G-reg ones are on a CAA national CofA and definitely cannot be maintained as a “homebuilt”.

Andreas IOM

In that case it is clearly not universally true. Interesting…

Administrator
Shoreham EGKA, United Kingdom
20 Posts
Sign in to add your message

Back to Top